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          <h2 class="post-title" itemprop="name headline">JavaScript 基础

              
            
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        <p>JavaScript 基础语法介绍，基于 ES6。</p>
<p>必须启用严格模式</p>
<figure class="highlight js"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br><span class="line">3</span><br></pre></td><td class="code"><pre><span class="line"><span class="meta">'use strict'</span></span><br><span class="line"></span><br><span class="line"><span class="comment">// code</span></span><br></pre></td></tr></table></figure>
<a id="more"></a>
<h1 id="数据类型-6-种"><a href="#数据类型-6-种" class="headerlink" title="数据类型(6 种)"></a>数据类型(6 种)</h1><ul>
<li><p><code>Number</code></p>
</li>
<li><p><code>String</code></p>
</li>
<li><p><code>Boolean</code></p>
</li>
<li><p><code>Array</code></p>
</li>
<li><p><code>null</code></p>
</li>
<li><p><code>undefined</code></p>
</li>
<li><p><code>Object</code> 包含 <code>function</code> <code>Date</code> <code>Array</code></p>
</li>
</ul>
<figure class="highlight js"><table><tr><td class="gutter"><pre><span class="line">1</span><br></pre></td><td class="code"><pre><span class="line"><span class="keyword">let</span> x = <span class="keyword">new</span> <span class="built_in">Number</span>;</span><br></pre></td></tr></table></figure>
<h2 id="类型转换"><a href="#类型转换" class="headerlink" title="类型转换"></a>类型转换</h2><figure class="highlight js"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br><span class="line">3</span><br></pre></td><td class="code"><pre><span class="line"><span class="built_in">String</span>(<span class="number">123</span>);</span><br><span class="line"></span><br><span class="line">(<span class="number">123</span>).toString()</span><br></pre></td></tr></table></figure>
<h2 id="类型检测"><a href="#类型检测" class="headerlink" title="类型检测"></a>类型检测</h2><figure class="highlight javascript"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br><span class="line">3</span><br><span class="line">4</span><br><span class="line">5</span><br><span class="line">6</span><br><span class="line">7</span><br><span class="line">8</span><br><span class="line">9</span><br></pre></td><td class="code"><pre><span class="line"><span class="keyword">typeof</span> <span class="number">100</span> <span class="comment">// number</span></span><br><span class="line"></span><br><span class="line">obj <span class="keyword">instanceof</span> <span class="built_in">Object</span> <span class="comment">// obj 是不是 Object</span></span><br><span class="line"></span><br><span class="line"><span class="built_in">Object</span>.prototype.toString.apply([]); <span class="comment">// [object Array]</span></span><br><span class="line"></span><br><span class="line"><span class="comment">// constructor</span></span><br><span class="line"></span><br><span class="line"><span class="comment">// duck type</span></span><br></pre></td></tr></table></figure>
<h2 id="隐式转换"><a href="#隐式转换" class="headerlink" title="隐式转换"></a>隐式转换</h2><figure class="highlight javascript"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br><span class="line">3</span><br></pre></td><td class="code"><pre><span class="line"><span class="string">"37"</span> - <span class="number">7</span> <span class="comment">// 30</span></span><br><span class="line"></span><br><span class="line"><span class="string">"37"</span> + <span class="number">7</span> <span class="comment">// 377</span></span><br></pre></td></tr></table></figure>
<h1 id="基础语法"><a href="#基础语法" class="headerlink" title="基础语法"></a>基础语法</h1><ul>
<li>一行或多行 字符串和变量写在一起</li>
</ul>
<figure class="highlight js"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br><span class="line">3</span><br><span class="line">4</span><br></pre></td><td class="code"><pre><span class="line"><span class="string">`your name is <span class="subst">$&#123;name&#125;</span>`</span></span><br><span class="line"></span><br><span class="line"><span class="string">`h</span></span><br><span class="line"><span class="string">ello JS`</span></span><br></pre></td></tr></table></figure>
<ul>
<li><p>常量 <code>const PI=3.14; // 同 PHP</code></p>
</li>
<li><p>变量 <code>let a;</code> <code>a = 1</code> <code>a = &#39;Hello World !&#39;</code></p>
</li>
</ul>
<p><code>let</code> <code>const</code> 严禁使用 <code>var</code></p>
<ul>
<li><p>特例 <code>var a = (1,2,3); // 取右边的数值 a = 3</code></p>
</li>
<li><p>连接符 <code>+</code></p>
</li>
<li><p>换行</p>
</li>
</ul>
<figure class="highlight js"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br></pre></td><td class="code"><pre><span class="line"><span class="built_in">document</span>.write(<span class="string">"hello \</span></span><br><span class="line"><span class="string">World !"</span>)</span><br></pre></td></tr></table></figure>
<h1 id="调试"><a href="#调试" class="headerlink" title="调试"></a>调试</h1><figure class="highlight js"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br><span class="line">3</span><br></pre></td><td class="code"><pre><span class="line"><span class="keyword">let</span> x = <span class="number">15</span> * <span class="number">5</span>;</span><br><span class="line"><span class="keyword">debugger</span>;</span><br><span class="line"><span class="built_in">document</span>.getElementbyId(<span class="string">"demo"</span>).innerHTML = x;</span><br></pre></td></tr></table></figure>
<h1 id="变量提升"><a href="#变量提升" class="headerlink" title="变量提升"></a>变量提升</h1><figure class="highlight js"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br><span class="line">3</span><br><span class="line">4</span><br><span class="line">5</span><br><span class="line">6</span><br><span class="line">7</span><br><span class="line">8</span><br><span class="line">9</span><br></pre></td><td class="code"><pre><span class="line">a = <span class="number">1</span>;</span><br><span class="line"></span><br><span class="line"><span class="built_in">console</span>.log(a); <span class="comment">// 可以正常输出</span></span><br><span class="line"></span><br><span class="line"><span class="built_in">console</span>.log(b); <span class="comment">// 报错</span></span><br><span class="line"></span><br><span class="line"><span class="keyword">var</span> a;</span><br><span class="line"></span><br><span class="line"><span class="keyword">var</span> b = <span class="number">1</span>; <span class="comment">// 声明的同时赋值，变量不会提升</span></span><br></pre></td></tr></table></figure>
<h2 id="变量作用域"><a href="#变量作用域" class="headerlink" title="变量作用域"></a>变量作用域</h2><p>函数外部声明，函数内部可以调用，反之不行。</p>
<p>特例：如果变量在函数内没有声明（即，没有使用 <code>var</code> 关键字），该变量为全局变量</p>
<figure class="highlight js"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br><span class="line">3</span><br><span class="line">4</span><br><span class="line">5</span><br><span class="line">6</span><br></pre></td><td class="code"><pre><span class="line"><span class="comment">// 此处可调用 carName 变量</span></span><br><span class="line"></span><br><span class="line"><span class="function"><span class="keyword">function</span> <span class="title">myFunction</span>(<span class="params"></span>) </span>&#123;</span><br><span class="line">    carName = <span class="string">"Volvo"</span>;</span><br><span class="line">    <span class="comment">// 此处可调用 carName 变量</span></span><br><span class="line">&#125;</span><br></pre></td></tr></table></figure>
<h1 id="函数"><a href="#函数" class="headerlink" title="函数"></a>函数</h1><figure class="highlight js"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br><span class="line">3</span><br><span class="line">4</span><br><span class="line">5</span><br><span class="line">6</span><br><span class="line">7</span><br><span class="line">8</span><br></pre></td><td class="code"><pre><span class="line"><span class="function"><span class="keyword">function</span> <span class="title">fun1</span>(<span class="params">a, b = <span class="number">3</span></span>) </span>&#123; <span class="comment">// ES6 才允许函数默认值</span></span><br><span class="line">  <span class="built_in">console</span>.log(a);</span><br><span class="line">  <span class="built_in">console</span>.log(b);</span><br><span class="line">  argument[<span class="number">0</span>];     <span class="comment">// 包含函数参数的数组</span></span><br><span class="line">  <span class="keyword">return</span> a;        <span class="comment">// 函数返回值</span></span><br><span class="line">&#125;</span><br><span class="line"></span><br><span class="line">fun1(<span class="number">1</span>, <span class="number">2</span>);  <span class="comment">// 调用函数</span></span><br></pre></td></tr></table></figure>
<p>在函数表达式存储在变量后，变量也可作为一个函数使用：</p>
<figure class="highlight js"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br></pre></td><td class="code"><pre><span class="line"><span class="keyword">let</span> x = <span class="function"><span class="keyword">function</span> (<span class="params">a, b</span>) </span>&#123;<span class="keyword">return</span> a * b&#125;;</span><br><span class="line"><span class="keyword">let</span> z = x(<span class="number">4</span>, <span class="number">3</span>);</span><br></pre></td></tr></table></figure>
<h2 id="函数参数"><a href="#函数参数" class="headerlink" title="函数参数"></a>函数参数</h2><h3 id="可变参数-ES6-同-PHP"><a href="#可变参数-ES6-同-PHP" class="headerlink" title="可变参数 ES6 同 PHP"></a>可变参数 <code>ES6</code> 同 PHP</h3><figure class="highlight js"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br><span class="line">3</span><br><span class="line">4</span><br><span class="line">5</span><br></pre></td><td class="code"><pre><span class="line"><span class="function"><span class="keyword">function</span> <span class="title">f</span>(<span class="params">...a</span>)</span>&#123;</span><br><span class="line">  <span class="comment">// 遍历 a</span></span><br><span class="line">&#125;</span><br><span class="line"></span><br><span class="line">f(<span class="number">1</span>,<span class="number">2</span>,<span class="number">3</span>,<span class="number">4</span>);</span><br></pre></td></tr></table></figure>
<h2 id="自调用函数"><a href="#自调用函数" class="headerlink" title="自调用函数"></a>自调用函数</h2><figure class="highlight js"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br><span class="line">3</span><br></pre></td><td class="code"><pre><span class="line">(<span class="function"><span class="keyword">function</span> (<span class="params"></span>) </span>&#123;</span><br><span class="line">    <span class="keyword">let</span> x = <span class="string">"Hello!!"</span>;      <span class="comment">// 我将调用自己</span></span><br><span class="line">&#125;)();</span><br></pre></td></tr></table></figure>
<h2 id="闭包"><a href="#闭包" class="headerlink" title="闭包"></a>闭包</h2><figure class="highlight js"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br></pre></td><td class="code"><pre><span class="line"></span><br><span class="line"></span><br></pre></td></tr></table></figure>
<h2 id="高阶函数"><a href="#高阶函数" class="headerlink" title="高阶函数"></a>高阶函数</h2><p>一个函数接收另一个函数作为参数，这种函数就称之为高阶函数</p>
<h2 id="箭头函数"><a href="#箭头函数" class="headerlink" title="箭头函数"></a>箭头函数</h2><figure class="highlight js"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br><span class="line">3</span><br><span class="line">4</span><br><span class="line">5</span><br><span class="line">6</span><br><span class="line">7</span><br><span class="line">8</span><br><span class="line">9</span><br><span class="line">10</span><br><span class="line">11</span><br><span class="line">12</span><br><span class="line">13</span><br><span class="line">14</span><br><span class="line">15</span><br><span class="line">16</span><br><span class="line">17</span><br><span class="line">18</span><br><span class="line">19</span><br><span class="line">20</span><br><span class="line">21</span><br><span class="line">22</span><br><span class="line">23</span><br><span class="line">24</span><br><span class="line">25</span><br><span class="line">26</span><br><span class="line">27</span><br><span class="line">28</span><br><span class="line">29</span><br></pre></td><td class="code"><pre><span class="line">x =&gt; x * x</span><br><span class="line"></span><br><span class="line"><span class="function"><span class="keyword">function</span> (<span class="params">x</span>) </span>&#123;</span><br><span class="line">    <span class="keyword">return</span> x * x;</span><br><span class="line">&#125;</span><br><span class="line"></span><br><span class="line">x =&gt; &#123;</span><br><span class="line">    <span class="keyword">if</span> (x &gt; <span class="number">0</span>) &#123;</span><br><span class="line">        <span class="keyword">return</span> x * x;</span><br><span class="line">    &#125;</span><br><span class="line">    <span class="keyword">else</span> &#123;</span><br><span class="line">        <span class="keyword">return</span> - x * x;</span><br><span class="line">    &#125;</span><br><span class="line">&#125;</span><br><span class="line"></span><br><span class="line"><span class="comment">// 两个参数:</span></span><br><span class="line">(x, y) =&gt; x * x + y * y</span><br><span class="line"></span><br><span class="line"><span class="comment">// 无参数:</span></span><br><span class="line">() =&gt; <span class="number">3.14</span></span><br><span class="line"></span><br><span class="line"><span class="comment">// 可变参数:</span></span><br><span class="line">(x, y, ...rest) =&gt; &#123;</span><br><span class="line">    <span class="keyword">var</span> i, sum = x + y;</span><br><span class="line">    <span class="keyword">for</span> (i=<span class="number">0</span>; i&lt;rest.length; i++) &#123;</span><br><span class="line">        sum += rest[i];</span><br><span class="line">    &#125;</span><br><span class="line">    <span class="keyword">return</span> sum;</span><br><span class="line">&#125;</span><br></pre></td></tr></table></figure>
<h1 id="包装对象"><a href="#包装对象" class="headerlink" title="包装对象"></a>包装对象</h1><figure class="highlight javascript"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br><span class="line">3</span><br></pre></td><td class="code"><pre><span class="line"><span class="keyword">let</span> a = <span class="string">'a'</span>;</span><br><span class="line"></span><br><span class="line"><span class="keyword">let</span> obj = <span class="keyword">new</span> <span class="built_in">String</span>(<span class="string">'a'</span>);</span><br></pre></td></tr></table></figure>
<h1 id="数组"><a href="#数组" class="headerlink" title="数组"></a>数组</h1><figure class="highlight javascript"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br><span class="line">3</span><br><span class="line">4</span><br><span class="line">5</span><br><span class="line">6</span><br><span class="line">7</span><br><span class="line">8</span><br><span class="line">9</span><br><span class="line">10</span><br><span class="line">11</span><br></pre></td><td class="code"><pre><span class="line"><span class="keyword">let</span> myArray = <span class="keyword">new</span> <span class="built_in">Array</span>();</span><br><span class="line"></span><br><span class="line"><span class="keyword">let</span> myArray = <span class="keyword">new</span> <span class="built_in">Array</span>(<span class="number">1</span>,<span class="number">2</span>,<span class="number">3</span>);</span><br><span class="line"></span><br><span class="line"><span class="keyword">let</span> myArray = [<span class="number">1</span>,<span class="number">2</span>,<span class="number">3</span>]; <span class="comment">// 同 PHP</span></span><br><span class="line"></span><br><span class="line">myArray[<span class="number">0</span>] = <span class="number">80</span>;  <span class="comment">// 数组赋值</span></span><br><span class="line"></span><br><span class="line">myArray.length;  <span class="comment">// 数组长度</span></span><br><span class="line"></span><br><span class="line">myArray.sort()   <span class="comment">// 数组排序</span></span><br></pre></td></tr></table></figure>
<h2 id="数组合并"><a href="#数组合并" class="headerlink" title="数组合并"></a>数组合并</h2><figure class="highlight js"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br><span class="line">3</span><br></pre></td><td class="code"><pre><span class="line"><span class="keyword">let</span> a = [<span class="number">1</span>, <span class="number">2</span>, <span class="number">3</span>];</span><br><span class="line"></span><br><span class="line"><span class="keyword">let</span> b = [<span class="string">'hello'</span>, ...a];</span><br></pre></td></tr></table></figure>
<h1 id="流程控制"><a href="#流程控制" class="headerlink" title="流程控制"></a>流程控制</h1><p><code>if</code> <code>while</code> 同 PHP <code>break</code> <code>continue</code></p>
<figure class="highlight javascript"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br><span class="line">3</span><br><span class="line">4</span><br><span class="line">5</span><br><span class="line">6</span><br><span class="line">7</span><br></pre></td><td class="code"><pre><span class="line"><span class="keyword">switch</span> (expression) &#123;</span><br><span class="line">  <span class="keyword">case</span> expression: <span class="comment">// 这里是恒等 ===</span></span><br><span class="line"></span><br><span class="line">    <span class="keyword">break</span>;</span><br><span class="line">  <span class="keyword">default</span>:</span><br><span class="line"></span><br><span class="line">&#125;</span><br></pre></td></tr></table></figure>
<figure class="highlight javascript"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br><span class="line">3</span><br></pre></td><td class="code"><pre><span class="line"><span class="keyword">for</span> (<span class="keyword">let</span> i = <span class="number">0</span>; i &lt; array.length; i++) &#123;</span><br><span class="line">  array[i]</span><br><span class="line">&#125;</span><br></pre></td></tr></table></figure>
<figure class="highlight javascript"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br><span class="line">3</span><br><span class="line">4</span><br><span class="line">5</span><br></pre></td><td class="code"><pre><span class="line"><span class="keyword">for</span> (<span class="keyword">let</span> variable <span class="keyword">in</span> object) &#123;</span><br><span class="line">  <span class="keyword">if</span> (object.hasOwnProperty(variable)) &#123;</span><br><span class="line"></span><br><span class="line">  &#125;</span><br><span class="line">&#125;</span><br></pre></td></tr></table></figure>
<figure class="highlight javascript"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br><span class="line">3</span><br></pre></td><td class="code"><pre><span class="line"><span class="keyword">do</span> &#123;</span><br><span class="line"></span><br><span class="line">&#125; <span class="keyword">while</span> (<span class="literal">true</span>);</span><br></pre></td></tr></table></figure>
<h1 id="错误处理"><a href="#错误处理" class="headerlink" title="错误处理"></a>错误处理</h1><figure class="highlight js"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br><span class="line">3</span><br><span class="line">4</span><br><span class="line">5</span><br><span class="line">6</span><br><span class="line">7</span><br></pre></td><td class="code"><pre><span class="line"><span class="keyword">try</span> &#123;</span><br><span class="line">  <span class="keyword">throw</span> <span class="string">"test"</span></span><br><span class="line">&#125; <span class="keyword">catch</span> (e) &#123;</span><br><span class="line">  <span class="built_in">console</span>.log(e);</span><br><span class="line">&#125; <span class="keyword">finally</span> &#123;</span><br><span class="line">  <span class="built_in">console</span>.log(<span class="string">'finally'</span>);</span><br><span class="line">&#125;</span><br></pre></td></tr></table></figure>
<h1 id="严格模式-39-use-strict-39"><a href="#严格模式-39-use-strict-39" class="headerlink" title="严格模式 &#39;use strict&#39;"></a>严格模式 <code>&#39;use strict&#39;</code></h1><p>提供更强的错误检查。</p>
<figure class="highlight js"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br><span class="line">3</span><br></pre></td><td class="code"><pre><span class="line"><span class="function"><span class="keyword">function</span> <span class="title">functionName</span>(<span class="params"></span>) </span>&#123;</span><br><span class="line"><span class="meta">  'use strict'</span></span><br><span class="line">&#125;</span><br></pre></td></tr></table></figure>
<p>不允许用 <code>with</code></p>
<p><code>delete</code> 参数、函数名会报错</p>
<p>对象字面量重复属性报错 <code>{x:1,x:2}</code></p>
<p>等等。</p>

      
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                      hits: hits,
                      start: start,
                      end: end,
                      searchTextCount: searchTextCountInSlice
                    };
                  }

                  var slicesOfTitle = [];
                  if (indexOfTitle.length != 0) {
                    slicesOfTitle.push(mergeIntoSlice(title, 0, title.length, indexOfTitle));
                  }

                  var slicesOfContent = [];
                  while (indexOfContent.length != 0) {
                    var item = indexOfContent[indexOfContent.length - 1];
                    var position = item.position;
                    var word = item.word;
                    // cut out 100 characters
                    var start = position - 20;
                    var end = position + 80;
                    if(start < 0){
                      start = 0;
                    }
                    if (end < position + word.length) {
                      end = position + word.length;
                    }
                    if(end > content.length){
                      end = content.length;
                    }
                    slicesOfContent.push(mergeIntoSlice(content, start, end, indexOfContent));
                  }

                  // sort slices in content by search text's count and hits' count

                  slicesOfContent.sort(function (sliceLeft, sliceRight) {
                    if (sliceLeft.searchTextCount !== sliceRight.searchTextCount) {
                      return sliceRight.searchTextCount - sliceLeft.searchTextCount;
                    } else if (sliceLeft.hits.length !== sliceRight.hits.length) {
                      return sliceRight.hits.length - sliceLeft.hits.length;
                    } else {
                      return sliceLeft.start - sliceRight.start;
                    }
                  });

                  // select top N slices in content

                  var upperBound = parseInt('1');
                  if (upperBound >= 0) {
                    slicesOfContent = slicesOfContent.slice(0, upperBound);
                  }

                  // highlight title and content

                  function highlightKeyword(text, slice) {
                    var result = '';
                    var prevEnd = slice.start;
                    slice.hits.forEach(function (hit) {
                      result += text.substring(prevEnd, hit.position);
                      var end = hit.position + hit.length;
                      result += '<b class="search-keyword">' + text.substring(hit.position, end) + '</b>';
                      prevEnd = end;
                    });
                    result += text.substring(prevEnd, slice.end);
                    return result;
                  }

                  var resultItem = '';

                  if (slicesOfTitle.length != 0) {
                    resultItem += "<li><a href='" + articleUrl + "' class='search-result-title'>" + highlightKeyword(title, slicesOfTitle[0]) + "</a>";
                  } else {
                    resultItem += "<li><a href='" + articleUrl + "' class='search-result-title'>" + title + "</a>";
                  }

                  slicesOfContent.forEach(function (slice) {
                    resultItem += "<a href='" + articleUrl + "'>" +
                      "<p class=\"search-result\">" + highlightKeyword(content, slice) +
                      "...</p>" + "</a>";
                  });

                  resultItem += "</li>";
                  resultItems.push({
                    item: resultItem,
                    searchTextCount: searchTextCount,
                    hitCount: hitCount,
                    id: resultItems.length
                  });
                }
              })
            };
            if (keywords.length === 1 && keywords[0] === "") {
              resultContent.innerHTML = '<div id="no-result"><i class="fa fa-search fa-5x"></i></div>'
            } else if (resultItems.length === 0) {
              resultContent.innerHTML = '<div id="no-result"><i class="fa fa-frown-o fa-5x"></i></div>'
            } else {
              resultItems.sort(function (resultLeft, resultRight) {
                if (resultLeft.searchTextCount !== resultRight.searchTextCount) {
                  return resultRight.searchTextCount - resultLeft.searchTextCount;
                } else if (resultLeft.hitCount !== resultRight.hitCount) {
                  return resultRight.hitCount - resultLeft.hitCount;
                } else {
                  return resultRight.id - resultLeft.id;
                }
              });
              var searchResultList = '<ul class=\"search-result-list\">';
              resultItems.forEach(function (result) {
                searchResultList += result.item;
              })
              searchResultList += "</ul>";
              resultContent.innerHTML = searchResultList;
            }
          }

          if ('auto' === 'auto') {
            input.addEventListener('input', inputEventFunction);
          } else {
            $('.search-icon').click(inputEventFunction);
            input.addEventListener('keypress', function (event) {
              if (event.keyCode === 13) {
                inputEventFunction();
              }
            });
          }

          // remove loading animation
          $(".local-search-pop-overlay").remove();
          $('body').css('overflow', '');

          proceedsearch();
        }
      });
    }

    // handle and trigger popup window;
    $('.popup-trigger').click(function(e) {
      e.stopPropagation();
      if (isfetched === false) {
        searchFunc(path, 'local-search-input', 'local-search-result');
      } else {
        proceedsearch();
      };
    });

    $('.popup-btn-close').click(onPopupClose);
    $('.popup').click(function(e){
      e.stopPropagation();
    });
    $(document).on('keyup', function (event) {
      var shouldDismissSearchPopup = event.which === 27 &&
        $('.search-popup').is(':visible');
      if (shouldDismissSearchPopup) {
        onPopupClose();
      }
    });
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